1. Field of the Invention
The present invention relates to an apparatus and method for processing a product. More particularly, the present invention relates to a bottom-unloading product basket for placement in a processing vessel and methods using same.
2. Description of Related Technology
Processing products in treatment vessels is known in the art for many applications and in many industries. For example, cooking a food product through exposure to culinary steam, at either elevated pressure or at ambient atmospheric pressure, has been known for many years. Prior art steam-cooking processes often include a method for using the steam as a transfer medium for infusing the food product with spices and flavorings. Moreover, various methods exist for mechanically mixing a cooked food product to attain uniform texture, consistency and taste.
For instance, U.S. Pat. No. 5,993,878 discloses an apparatus and method of producing a food product. The food product is placed inside an air-tight chamber, in which the food product is to be cooked, wherein steam is generated from a source of water and is introduced into the cooking chamber. The steam heats the inside of the cooking chamber and serves as a heat transfer medium to heat the food product as well as a color and flavor transfer medium to color and flavor the food product. Flavoring and coloring additive, such as liquid smoke, may be added to the water utilized in generating the steam in order to flavor the food product being cooked. The steam then transfers the flavoring and coloring additive to the food product which condenses on the food product adding flavor and color to the food product.
U.S. Pat. No. 5,794,524 discloses a food processor with a mixing vessel and a drive mechanism for an agitator in the mixing vessel, the lower region of which can be heated. A top unit for the mixing vessel has a perforated base to allow food to be steam-cooked. The perforations are formed in a support plate in the base of the top unit and condensation and moisture are led back into the mixing vessel.
U.S. Pat. No. 5,653,161 discloses a food steamer having a base, a combined support and collector, and a cooking bowl. The base has a heater and a reservoir for holding water to be heated into steam. The cooking bowl is mounted on top of the base and has a bottom with holes. The combined support and collector has a frame and a screen. The frame is mounted to the base between the heater and the cooking bowl. The frame has a center aperture with the screen located therein for supporting flavoring items thereon. The frame has raised walls to form a condensed steam holding area for holding all condensed steam that has traveled into and then back out of the holes in the cooking bowl. The frame also has a side wall with inwardly recessed grooves and holes through the frame at the tops of the grooves. These form pressure release vents at the sides of the frame.
U.S. Pat. No. 5,584,235 discloses a food steamer having a base, a combined support and collector, and a cooking bowl. The base has a heater and a reservoir for holding water to be heated into steam. The cooking bowl is mounted on top of the base and has a bottom with holes. The combined support and collector has a frame and a screen. The frame is mounted to the base between the heater and the cooking bowl. The frame has a center aperture with the screen located therein for supporting flavoring items thereon. The frame has raised walls to form a condensed steam holding area for holding all condensed steam that has traveled into and then back out of the holes in the cooking bowl.
Ordinarily, steam-cooking involves placing a food product within or on a bowl-shaped apparatus having a plurality of small holes throughout the bottom surface and sides, and either positioning the apparatus above a quantity of potable water that is heated into steam or placing the apparatus within a covered vessel into which culinary steam is introduced. Typically, the bottom surface of the bowl-shaped apparatus holding or containing the food product to be steam-cooked is integrally fastened to the sides thereof, and has a plurality of small holes that allow steam, but not food product, to pass through. Removal of the food product from the bowl-shaped apparatus after completion of the steam-cooking process usually involves the tilting or inversion of the apparatus to release the food product. In addition, steam-cooking of a food product often is performed in a closed vessel under elevated atmospheric pressure.
Moreover, certain food products may be subjected to further processing subsequent to steam-cooking. For example, it may be desirable for a food product that has been steam-cooked at elevated atmospheric pressure then to be mechanically mixed at a non-elevated pressure, either to add spices or flavorings or to attain a uniform or otherwise more desirable taste, texture or consistency. To subject the steamed food product to a mechanical mixing process, the food product usually is transferred from the cooking vessel in which the steam-cooking was performed into a second cooking vessel in which mechanical mixing will be performed. Such transfer commonly is accomplished through the use of vessel-to-vessel pipes and pipe pumping equipment or through the hoisting and removal of the food product from the first vessel and placement into the second vessel. Furthermore, the second vessel may be equipped with integrally-attached agitators, blades or scrapers to mix or blend the steam-cooked food product. The need for multiple vessels for such multi-step processing is particularly evident where the first cooking vessel is designed and equipped to steam-cook food products at elevated pressure in a closed environment and the subsequent mechanical food product mixing step also needs to be accomplished in a covered vessel but at ambient atmospheric pressure.
In commercial-scale food processing operations, it is common for food products to be steam-cooked in very large batches by placing the food products into a large, bowl-shaped, perforated apparatus that is, in turn, placed into a closable cooking vessel having a capacity of 50 gallons or more. Such large quantities of food product can weigh hundreds of pounds or more and thus typically necessitate the use of sophisticated hoisting and tilting equipment, not only to remove the bowl-shaped apparatus from the cooking vessel after completion of the steam-cooking step, but also to remove the cooked food product from the bowl-shaped apparatus itself, and then to place the cooked food product into a second vessel for mechanical mixing, blending or other further processing.
In addition, selected flavors are often added to food products during steam-cooking processes, typically either by placing the whole, non-extract, non-concentrate form of spices (e.g., whole bay leaves, whole vanilla beans, whole peppercorns) directly into a covered vessel in which steam-cooking occurs or into a closed, perforated container that is placed within the vessel, thereby facilitating steam-infusion of the spices into the food product. Alternatively, flavoring of food products during steam-cooking processes is frequently accomplished through the addition of an extract, concentrate form of spices directly into the food product, thereby enabling the spices to be fully absorbed into the food product.
As will be appreciated by one of ordinary skill in the art, there are numerous other industries and fields wherein a product is processed in one or more treatment vessels. For example, it is common in the commercial waste management industry for waste materials to be treated to reduce the toxicity or mobility of chemical compounds in such materials by subjecting the materials to thermal energy within a closed vessel and subsequently subjecting the materials to further treatment, such as mechanical mixing or agitation, in the same or a second vessel. Similarly, concrete production or mining-related activities may involve the use of multiple vessels to accomplish heating and subsequent mixing or sorting of naturally-occurring materials such as sand or rocks.
The foregoing underscores some of the problems associated with conventional product processing techniques which require multiple vessels and/or lifting and/or tilting equipment. Furthermore, the foregoing highlights the need for an apparatus and method for processing a product using a bottom-unloading product basket which may preclude the need for multiple vessels and/or lifting and/or tilting equipment to process the product.
For example, the prior art does not disclose an apparatus nor a method that enables both steam-cooking at above-atmospheric pressure and mechanical mixing at ambient atmospheric pressure to be performed sequentially in a single covered vessel. Instead, it is typical in the food processing industry to use a separate vessel or container for each of the separate food processing steps that are applied to a particular food product, such as pressurized steam-cooking and non-pressurized mixing or blending. Moreover, prior art does not disclose an apparatus nor a method that enables a food product to be directly released from the bottom of a steamer basket apparatus without the need to invert or tilt such basket so as to discharge its food product contents. Instead, it is typical for the bottom surface of a steamer basket apparatus to be integrally fastened to the sides thereof, and not to be designed to be opened or otherwise separated from such sides, thereby necessitating the use of complex and expensive hoisting and tilting equipment to remove cooked food product from such an apparatus, particularly during commercial-scale processing of large quantities of food product.
The need to purchase, operate and maintain hoisting and tilting equipment to remove steam-cooked food product from a steamer basket, as well as the common practice of using multiple vessels to accomplish multi-step processing of a food product, add undesirable inefficiency, time, expense and food handling steps to the food preparation process. The additional exposure, handling and movement of food product, in turn, tend to cause loss of minerals, vitamins, spices and the like, and thus diminish the nutritional value and flavor of the steam-cooked food, and to increase the risk that the food product may be exposed to harmful bacteria during processing.
In addition, prior art does not disclose an apparatus nor a method that both enables the whole, non-extract, non-concentrate form of spices to be used to steam-infuse flavor into a food product within a cooking vessel, and further enables such spices to be removed from the vessel following completion of the steam-cooking process without the need to filter the cooked food product. On the other hand, where flavor enhancement of steam-cooked food product is accomplished through the use of the extract form of spices, no filtration or removal of the spices is required, but the extracts frequently contain undesirable additives, including alcohols, resins and oils, that are necessary to promote the absorption of the spice into the food product.
In light of the foregoing shortcomings and limitations of the prior art, a need exists for an apparatus that can hold food product while the food product is steam-cooked at above-atmospheric pressure in a closed cooking vessel, and which apparatus is bottom-unloading and therefore can be removed from the cooking vessel upon completion of the steam-cooking process without having to remove any of the food product from the cooking vessel as well. A further need exists for a method that enables food product to be both steam-cooked at above-atmospheric pressure and then mechanically mixed at ambient atmospheric pressure in a single closed vessel. An additional need exists for a method that enables food product in a closed vessel to be steam-infused with selected flavors using whole spices that may be easily removed from the vessel and that need not be filtered out of the cooked food product.
It is a primary object of the present invention to overcome the aforementioned shortcomings and limitations associated with the prior art by providing a new apparatus and method for processing a product. In accordance with this object of the invention, there is provided an apparatus for processing a product comprising a bottom-unloading product basket adapted for insertion in a treatment vessel. According to this aspect of the invention, a feature of the invention allows product treated in the basket to be unloaded and the basket removed from the vessel without the need for lifting or tilting equipment, whereby the product may be subjected to further processing in the same vessel.
It is another object of the invention to provide a new apparatus and method for processing food products. According to one aspect of the invention, there is provided an apparatus and method for preparing a food product through steam-cooking at above-atmospheric pressure followed by mechanical mixing of the steamed food product, at ambient atmospheric pressure, in a single covered vessel.
In accordance with another aspect of the present invention, there is provided an apparatus and method for preparing a food product in a single covered vessel, wherein a bottom-unloading perforated steamer basket holds the food product above the water level within the vessel during a steam-cooking process and, after completion of the steam-cooking process, all of the food product may be easily released from the bottom of the steamer basket directly into the vessel, and the empty steamer basket may then be removed from the vessel without having to remove any of the food product from the vessel as well.
In accordance with one advantageous feature of the invention, there is provided the aforementioned apparatus and method for preparing a food product in a single covered vessel, wherein a two-piece perforated steamer basket holds the food product above the water level within the vessel during a steam-cooking process and, after completion of the steam-cooking process, all of the food product may be easily released from the steamer basket directly into the vessel, and both pieces of the steamer basket may then be removed from the vessel without having to remove any of the food product from the vessel as well.
In accordance with another advantageous feature of the invention, there is provided the aforementioned apparatus and method for preparing a food product in a single covered vessel, wherein the vessel may be operated with either one of two domes secured in place, one of which is removably fastened to the top of the vessel during a pressurized steam-cooking process, and the other of which is removably fastened to the top of the vessel during a non-pressurized mechanical mixing process.
In accordance with yet another advantageous feature of the invention, there is provided the aforementioned apparatus and method for preparing a food product in a single covered vessel, wherein the source of the steam for cooking the food product is either a measured quantity of potable water which has been introduced into the bottom interior of the vessel, or culinary steam which has been introduced directly into the interior of the vessel, and wherein some or all of the water and other liquids remaining within the vessel after completion of the steam-cooking process is mixed with and fully incorporated into the food product during the mechanical mixing process, thereby restoring to the cooked food product nearly all nutrients, minerals and flavor that may have been lost or released from the food product during the steam-cooking process.
It is another feature of the invention is to provide the aforementioned apparatus and method for preparing a food product in a single covered vessel, wherein a perforated, closed container holding the whole, non-extract, non-concentrate form of various spices is removably fastened to a food product steamer basket at a point below the top of the water level in the vessel, to facilitate the infusion of selected flavors into the food product during the steam-cooking process and to enable the spices and container to be easily removed from the vessel simultaneously with removal of the steamer basket.
These and other objects, aspects and features of the invention may be realized by the provision of an apparatus comprising a bottom-unloading steamer basket which holds a product during processing within a covered treatment vessel, and which basket enables such product to be released directly from the bottom of the basket and into the vessel. Related objects may be realized by the provision of a method of processing a product through the application of both thermal energy at above atmospheric pressure and mechanical energy at ambient atmospheric pressure in a single covered treatment vessel.
As will be appreciated by one of ordinary skill in the art, an apparatus according to the invention may be suitable for use in any field or industry requiring the processing of a product in a treatment vessel. Accordingly, the present invention should not be viewed as limited to any particular use or use in any particular industry. Additional objects, advantages and novel features of the present invention will be set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.